Bushings and Switchgear

Abstract

To improve workability by updating only an insulator component and allowing all works in update of the insulator component from a switchgear room side.SOLUTION: In a bushing 7, a main circuit conductor 10 in which a switchgear 2 is connected to one side and a bus 5 and a cable 6 are connected to the other side is passed through and attached. The bushing 7 is composed of a plurality of divided insulator components 8A to 8F with the main circuit conductor 10 as a reference, and bushing attaching parts 14 and 15 for fixing the bushing 7 to a partition plate 30 and main circuit fastening parts 13, 16 and 17 for fastening the main circuit conductor 10 to the bushing 7 exist on a switchgear room 100A side.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present application relates to a bushing and a switchgear. [Background technology]

[0002] In the prior art, there is known a main circuit unit which is integrally assembled from a box-shaped fixed frame which accommodates a draw-out type circuit breaker so that it can be freely inserted and removed, upper and lower bushings which penetrate the rear wall of the fixed frame and face the upper and lower terminals which extend from the back surface of the circuit breaker, a main bus bar which is insulated and supported on the outer surface of either the top plate or the floor plate of the fixed frame, branch conductors which connect the main bus bar to the center conductor of the bushing on the side closer to the main bus bar, a through-type instrument current transformer and insulated and supported cable connection terminals which are fixed to the outer surface of the other of the top plate or the floor plate of the fixed frame, and connection conductors which penetrate the instrument current transformer and connect the center conductor of the bushing on the side closer to the instrument current transformer to the cable connection terminal, and the main circuit unit is housed in a housing, and an external cable which is drawn in from below or above the housing is connected to the cable connection terminal (see Patent Document 1 below).

[0003] When upgrading drawer-type fixed frames that house circuit breakers in the circuit breaker room of a switchboard due to reasons such as the end of their service life, conventional bushings required the busbar on the switchboard side to be disconnected from the main circuit conductor on the fixed frame side, even if only the insulator components were being replaced. When the busbar on the switchboard side and the main circuit conductor on the fixed frame side are disconnected, the entire fixed frame can be upgraded simply by removing the fastenings between the fixed frame and the switchboard floor. Furthermore, because disconnecting the main circuit requires traveling back and forth from the switchboard, the work takes longer and is more expensive. Therefore, the cost of the upgrade accounts for a large proportion of the cost, and the price of each component is not a major consideration, and there is little benefit to upgrading only the insulator components, it is common to replace the entire fixed frame. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-147566 Summary of the Invention [Problem to be solved by the invention]

[0005] Even with conventional bushings for each phase or pole, it is possible to remove the bushings if the fixing part of the main circuit conductor on the fixed frame side and the bushing are located in the circuit breaker room. However, it is difficult to position the main circuit conductor and bushing when installing the updated parts, so all work cannot be done from the circuit breaker room. The reason for this difficulty in positioning is that the circuit breaker room is separated from the busbar room and cable room by partition plates.

[0006] According to JEM1425, in PW class or higher distribution panels, each compartment must be separated by a partition plate. In a draw-out type circuit breaker, the rear plate of the fixed frame serves as the partition plate, and this corresponds to the rear plate of the fixed frame in Figure 2 of the above patent document. Because of the presence of this rear plate, it is not possible to support and adjust the position of the main circuit conductor on the fixed frame side and install insulating parts.

[0007] The aforementioned JEM standards are created by the Japan Electrical Manufacturers' Association (commonly known as JEMA), and JEM1425 is one such standard, specifying the requirements for specified metal-enclosed switchgear and control gear. Furthermore, PW class and above includes MW class and PW class. MW class is a switchgear in which each device is placed in a compartment separated by a grounded metal partition plate, and draw-out type devices are used. Specifically, the main circuit has a bushing structure and shutters, and the partition plate is structured to be attached with metal. PW class is a switchgear in which each device is placed in a compartment separated by a non-metallic partition plate, and draw-out type devices are used. Specifically, the main circuit has a bushing structure and shutters, and the partition plate is structured to be attached with non-metal.

[0008] This application discloses a technology for solving the above-mentioned problems, and aims to improve workability by enabling only the insulating components to be updated and enabling all work required for updating insulating components to be performed from the switchgear room side. [Means for solving the problem]

[0009] The bushing disclosed in the present application is fixed to a partition plate that separates a switchgear compartment that houses switchgear, a busbar compartment that houses busbars, and a cable compartment that houses cables, and is attached so that the switchgear is connected to one side and main circuit conductors to which the busbars and the cables are connected pass through the bushing to the other side, The bushing is composed of insulating parts divided into multiple pieces based on the main circuit conductor, and a bushing mounting portion that fixes the bushing to the partition plate and a main circuit conductor fastening portion that fastens the main circuit conductor to the bushing are located on the switchgear room side. The switchgear disclosed in the present application also includes the bushing, the switchgear device, the switchgear room that houses the switchgear device, the busbar room that houses the busbar and the cable room that houses the cable, the partition plate that separates the switchgear room from the busbar room and the cable room, and the main circuit conductor to which the switchgear device is connected on one side and to which the busbar and the cable are connected on the other side. [Effects of the Invention]

[0010] According to the bushing and switching device disclosed in the present application, it is possible to update only the insulating components, and all work required to update the insulating components can be performed from the switching equipment room side, thereby improving workability. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing an internal configuration of a switching device according to a first embodiment. [Figure 2]Fig. 2A is a perspective view for explaining a bushing with a divided structure according to embodiment 1. Fig. 2B is a perspective view showing a part of a main circuit conductor that penetrates and is attached to the bushing according to embodiment 1. [Figure 3] 10 is a diagram for explaining a state in which a bushing with a split structure according to the first embodiment is attached to a partition plate and a main circuit conductor is attached to the bushing. FIG. [Figure 4] Fig. 4A is a perspective view for explaining a bushing with a divided structure according to embodiment 2. Fig. 4B is a perspective view showing a part of a main circuit conductor that penetrates and is attached to the bushing according to embodiment 2. [Figure 5] 10 is a diagram for explaining a state in which a bushing with a split structure according to the second embodiment is attached to a partition plate and a main circuit conductor is attached to the bushing. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Embodiment 1 FIG. 1 is a schematic diagram showing the internal configuration of a switching device according to the first embodiment. In this embodiment, a closed switchboard is taken as an example of a switchgear, and a configuration in which a drawer-type circuit breaker is housed as a switching device inside the switchgear (closed switchboard) will be described.

[0013] 1, the interior of a housing 1 of a switchgear is divided into a plurality of chambers by partition plates 4. That is, a chamber in which a circuit breaker 2 serving as a switchgear is housed is a switchgear chamber 100A, a chamber in which a three-phase (R-phase, S-phase, T-phase) busbar 5 is housed is a busbar chamber 100B, and a chamber in which an external cable 6 is housed is a cable chamber 100C.

[0014] In the switchgear room 100A, drawer fixing frames 3 are installed in, for example, two stages, and circuit breakers 2 are arranged on each of the drawer fixing frames 3. The internal configuration of the circuit breakers 2 is not shown because it is publicly known. In the busbar chamber 100B, three-phase (R-phase, S-phase, T-phase) busbars 5 are arranged, and each busbar 5 is electrically connected to a main circuit conductor 10 (described later) via a terminal. Three-phase (R-phase, S-phase, T-phase) cables 6 are arranged in the cable room 100C, and each cable 6 is electrically connected to a main circuit conductor 10 (described later) via a terminal. The drawer fixing frame 3 is provided with a fixing frame partition plate 30 that is continuous with the partition plate 4, and this fixing frame partition plate 30 is adapted to be fitted with a bushing 7, which will be described later. The bushing 7 is adapted to receive a main circuit conductor 10 connected to the busbar 5 and the cable 6 therethrough. In the claims of the present application, the partition plate 4 and the fixed frame partition plate 30 are collectively referred to as the partition plate.

[0015] As will be described later, the bushing 7 of the present application is composed of insulating parts divided into multiple pieces based on the main circuit conductor 10, and a bushing mounting portion that fixes the bushing 7 to the fixed frame partition plate 30 and a main circuit conductor fastening portion that fastens the main circuit conductor 10 to the bushing 7 are located on the switchgear room 100A side.

[0016] FIG. 2A is a perspective view illustrating a bushing with a divided structure according to the first embodiment, and FIG. 2B is a perspective view showing a part of a main circuit conductor that penetrates and is attached to the bushing according to the first embodiment. FIG. 3 is a diagram for explaining how the bushing with a split structure according to the first embodiment is attached to a partition plate and how a main circuit conductor is attached to the bushing.

[0017] 2A, 2B, and 3, the main circuit conductor 10 has a first main circuit conductor 10A connected to a three-phase (R phase, S phase, T phase) bus bar 5 and a second main circuit conductor 10B connected to a cable 6 of the same phase as the bus bar 5, and the first main circuit conductor 10A and the second main circuit conductor 10B of the same phase are arranged in two tiers. The bushing 7A according to the first embodiment is divided by planes 8AB, 8CD, and 8EF, each including the central axis CL (see FIG. 2B) of the first main circuit conductor 10A arranged in two stages and the central axis CL (see FIG. 2B) of the second main circuit conductor 10B that is in phase with the first main circuit conductor 10A, and by planes 8BC and 8DE, each corresponding to the first main circuit conductor 10A and the second main circuit conductor 10B that are in phase with the first main circuit conductor 10A and the second main circuit conductor 10B. As a result, the bushing 7A is divided into a total of six insulator components 8A to 8F. Each of the six divided insulator components 8A to 8F has a bushing mounting hole 14, one on the top and one on the bottom.

[0018] As shown in FIG. 2A, the insulator components 8A to 8F are symmetrical in the vertical direction with respect to the center line X1-X1 in the Z direction (vertical direction). Furthermore, the pairs of insulator parts 8A and 8B, 8C and 8D, and 8E and 8F are symmetrical with respect to the planes 8AB, 8CD, and 8EF, respectively. With the above structure, only one mold is required to manufacture the insulating components 8A to 8F, thereby reducing costs.

[0019] Each pair of insulating parts 8A and 8B, 8C and 8D, and 8E and 8F has, at the top and bottom thereof sandwiching the center line X1-X1 in the Z direction, main circuit conductor mounting portions 11 for mounting the first main circuit conductor 10A and the second main circuit conductor 10B of the same phase, and an insulating tube 12 arranged to surround the main circuit conductor mounting portions 11.

[0020] The main circuit conductor fastening portions 13, 16, 17 are composed of a main circuit conductor mounting hole 13 provided in the main circuit conductor mounting portion 11, a main circuit conductor female thread portion 16 provided in the first main circuit conductor 10A and the second main circuit conductor 10B, and a main circuit conductor fastening bolt 17. The bushing mounting portions 14, 15 are composed of bushing mounting holes 14 and bushing mounting bolts 15 provided in each of the insulating components 8A to 8F.

[0021] Next, the operation of attaching the bushing having a split structure according to the first embodiment to the partition plate and attaching the main circuit conductor to the bushing will be described with reference to FIG. FIG. 3 shows a state in which three insulating parts 8A, 8B, and 8C are attached to the fixing frame partition plate 30 of the drawer fixing frame 3. The insulating components 8A, 8B, and 8C can be attached to the fixed frame partition plate 30 with bushing attachment bolts 15 using the bushing attachment holes 14 from the switchgear compartment 100A side. The first main circuit conductor 10A and the second main circuit conductor 10B can also be fastened to the insulating parts 8A, 8B, and 8C from the switchgear room 100A side using the main circuit conductor fastening bolts 17 via the main circuit conductor female thread portion 16 and the main circuit conductor mounting hole 13.

[0022] As described above, in this embodiment, the bushing mounting portions 14, 15, which are the mounting portions for the insulating parts 8A to 8F and the fixed frame partition plate 30, are located on the switching equipment room 100A side, making it possible to attach and detach the insulating parts 8A to 8F from the switching equipment room 100A side. Furthermore, since the main circuit conductor fastening portions 13, 16, 17, which are the fastening portions between the insulator components 8A to 8F and the first and second main circuit conductors 10A and 10B, are located on the switchgear room 100A side, all work involved in replacing the insulator components 8A to 8F can be performed from the switchgear room 100A side. This makes it possible to replace the insulating parts 8A to 8F without moving to the rear of the switchgear (distribution panel), and it is expected that the work time will be reduced.

[0023] Furthermore, as shown in FIG. 3, by attaching one of the pair of insulating parts 8C, 8D, 8C, to the fixed frame partition plate 30, the first main circuit conductor 10A and the second main circuit conductor 10B can be fastened and fixed using the main circuit conductor fastening bolt 17, eliminating the need for an operator to manually position the first main circuit conductor 10A and the second main circuit conductor 10B when replacing the bushings. With the above structure, it is possible to carry out work even when the fixed frame partition plate 30 prevents hands from reaching the bus room 100B and the cable room 100C.

[0024] Furthermore, the pairs of insulating parts 8A and 8B, 8C and 8D, and 8E and 8F are symmetrical on the left and right sides with respect to the planes 8AB, 8CD, and 8EF, respectively, so that the workability remains the same regardless of whether the worker starts work from the left or right side, and the structure also prevents variations in quality due to differences in workers.

[0025] In the above explanation, an example was shown in which bushing 7A is composed of six divided insulator parts 8A to 8F, but instead of insulator parts 8B and 8C, an insulator part in which insulator parts 8B and 8C are integrated may be provided, and instead of insulator parts 8D and 8E, an insulator part in which insulator parts 8D and 8E are integrated may be provided.

[0026] As described above, according to the first embodiment, the switchgear compartment, which houses the switchgear, the busbar compartment, which houses the busbar, and the cable compartment, which houses the cable, are fixed to the partition plate, and A bushing through which a main circuit conductor, to which the switching device is connected on one side and to which the bus bar and the cable are connected on the other side, is inserted and attached, The bushing is composed of insulating parts divided into multiple pieces based on the main circuit conductor, and a bushing mounting portion that fixes the bushing to the partition plate and a main circuit conductor fastening portion that fastens the main circuit conductor to the bushing are located on the switchgear room side, thereby achieving the following effects. In other words, by constructing the bushing from multiple insulator components separated based on the main circuit conductor, the position of the main circuit conductor can be determined by one of the insulator components when installing the main circuit conductor. This eliminates the difficulty of replacing individual insulator components in conventional systems, making it possible to replace only the insulator components. By replacing only the insulator components, there is no need to replace metal components that have not yet reached the end of their service life, reducing unnecessary costs. Furthermore, the ease of replacing insulator components also shortens the update cycle, which is expected to improve reliability. Furthermore, by locating the bushing mounting portion that fixes the bushing to the partition plate and the main circuit conductor fastening portion that fastens the main circuit conductor to the bushing on the switchgear room side, all work involved in replacing insulating parts can be performed from one side (the front side) of the switchgear, thereby shortening the work time.

[0027] The main circuit conductors include a first main circuit conductor connected to a three-phase bus bar and a second main circuit conductor connected to a cable of the same phase as the bus bar, and the first main circuit conductor and the second main circuit conductor of the same phase are arranged in two stages, The bushing is configured by the insulator parts divided by a plane including the central axes of the first main circuit conductor and the second main circuit conductor of the same phase, It is possible to provide a bushing structure that allows the work of replacing insulating parts to be performed more easily.

[0028] Furthermore, the bushing is configured by the insulator parts divided for the first main circuit conductor and the second main circuit conductor of the same phase, and all the insulator parts have the same shape. Costs can be reduced because only one mold is used to manufacture all insulating parts.

[0029] Embodiment 2 In the second embodiment, a description will be given of a divided structure of the bushing that is different from that of the first embodiment. Note that, since the other parts than the divided structure of the bushing are the same as those of the first embodiment, a description thereof will be omitted.

[0030] FIG. 4A is a perspective view illustrating a bushing with a divided structure according to a second embodiment, and FIG. 4B is a perspective view showing a part of a main circuit conductor that penetrates and is attached to the bushing according to the second embodiment. FIG. 5 is a diagram for explaining how a bushing having a split structure according to the second embodiment is attached to a partition plate and how a main circuit conductor is attached to the bushing.

[0031] 4A, 4B, and 5, the main circuit conductor 10 has a first main circuit conductor 10A connected to a three-phase (R phase, S phase, T phase) bus bar 5 and a second main circuit conductor 10B connected to a cable 6 of the same phase as the bus bar 5, and the first main circuit conductor 10A and the second main circuit conductor 10B of the same phase are arranged in two tiers. The bushing 7B according to the second embodiment is first divided by a plane 8GH including the central axes CL (see FIG. 4B) of the three-phase first main circuit conductors 10A arranged in the first tier, and is then divided by a plane 8IJ including the central axes CL (see FIG. 4B) of the three-phase second main circuit conductors 10B arranged in the second tier. The bushing 7B is further divided by a plane 8HI that separates the first tier, in which the first main circuit conductors 10A are arranged, from the second tier, in which the second main circuit conductors 10B are arranged. As a result, the bushing 7B is divided into a total of four insulator components 8G to 8J. Each of the four divided insulator components 8G to 8J has a bushing mounting hole 14.

[0032] As shown in FIG. 4A, the insulator components 8G to 8J have a structure that is symmetrical in the left-right direction (X direction) with respect to the center line Z1-Z1 in the X direction (left-right direction). Furthermore, the pairs of insulating parts 8G and 8H, and 8I and 8J are symmetrical in the vertical direction (Z direction) with respect to the planes 8GH and 8IJ, respectively. With the above structure, only one mold is required to manufacture the insulating part, thereby reducing costs.

[0033] A pair of insulating components 8G and 8H, and 8I and 8J are provided with a main circuit conductor mounting portion 11 for mounting the first main circuit conductor 10A and the second main circuit conductor 10B, and an insulating tube 12 arranged to surround the main circuit conductor mounting portion 11.

[0034] The main circuit conductor fastening portions 13, 16, 17 are composed of a main circuit conductor mounting hole 13 provided in the main circuit conductor mounting portion 11, a main circuit conductor female thread portion 16 provided in the first main circuit conductor 10A and the second main circuit conductor 10B, and a main circuit conductor fastening bolt 17. The bushing mounting portions 14, 15 are composed of bushing mounting holes 14 and bushing mounting bolts 15 provided in each of the insulating components 8G to 8J.

[0035] Next, the operation of attaching the bushing having a split structure according to the second embodiment to the partition plate and attaching the main circuit conductor to the bushing will be described with reference to FIG. FIG. 5 shows a state in which three insulating parts 8G, 8H, and 8J are attached to the fixing frame partition plate 30 of the drawer fixing frame 3. The insulating components 8G, 8H, and 8I can be attached to the fixed frame partition plate 30 with bushing attachment bolts 15 using the bushing attachment holes 14 from the switchgear compartment 100A side. The first main circuit conductor 10A and the second main circuit conductor 10B can also be fastened to the insulating parts 8G, 8H, and 8J from the switchgear room 100A side using the main circuit conductor fastening bolts 17 via the main circuit conductor female thread portion 16 and the main circuit conductor mounting hole 13.

[0036] As described above, in this embodiment, the bushing mounting portions 14, 15, which are the mounting portions for the insulating parts 8G to 8J and the fixed frame partition plate 30, are located on the switching equipment chamber 100A side, making it possible to attach and detach the insulating parts 8G to 8J from the switching equipment chamber 100A side. Furthermore, since the main circuit conductor fastening portions 13, 16, 17, which are the fastening portions between the insulator components 8G to 8J and the first and second main circuit conductors 10A and 10B, are located on the switchgear room 100A side, all work involved in replacing the insulator components 8G to 8J can be performed from the switchgear room 100A side. This makes it possible to replace insulating parts 8G to 8J without moving to the rear of the switchgear (distribution panel), which is expected to reduce work time.

[0037] Furthermore, as shown in Figure 5, if one of the pair of insulator parts 8I and 8J, 8J, is attached to the fixed frame partition plate 30, the three-phase second main circuit conductor 10B can be fastened and fixed using the main circuit conductor fastening bolt 17, and there is no need for the worker to position the second main circuit conductor 10B by hand or the like when replacing the bushing. With the above structure, it is possible to carry out work even when the fixed frame partition plate 30 prevents hands from reaching the bus room 100B and the cable room 100C.

[0038] Furthermore, compared with the insulator components 8A to 8F of the first embodiment, the number of insulator components 8G to 8J is smaller, and the number of operations is reduced, so that the operation time can be shortened.

[0039] In the above explanation, an example was shown in which bushing 7B is composed of four divided insulator parts 8G to 8J, but instead of insulator parts 8H and 8I, it may also be provided with an insulator part in which insulator parts 8H and 8I are integrated.

[0040] As described above, in the second embodiment, the main circuit conductors include a first main circuit conductor connected to a three-phase bus bar and a second main circuit conductor connected to a cable of the same phase as the bus bar, and the first main circuit conductors and the second main circuit conductors of the same phase are arranged in two stages, The bushing is configured by the insulator parts divided by a plane including the central axes of the first main circuit conductors of three phases and divided by a plane including the central axes of the second main circuit conductors of three phases, It is possible to provide a bushing structure that allows the work of replacing insulating parts to be performed more easily.

[0041] Furthermore, the bushing is configured by the insulator parts divided into two sections for the first main circuit conductors and the second main circuit conductors arranged in two stages, and all the insulator parts have the same shape. Costs can be reduced because only one mold is used to manufacture all insulating parts.

[0042] Although the present application describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are conceivable within the scope of the technology disclosed in this application, including, for example, cases where at least one component is modified, added, or omitted, and cases where at least one component is extracted and combined with a component of another embodiment. [Explanation of symbols]

[0043] 1 Switchgear housing, 2 Circuit breaker (switchgear), 3 Drawer fixing frame, 4 Partition plate, 5 busbar, 6 cable, 7, 7A, 7B bushing, 8A~8F insulating parts, 8G~8J insulating parts, 10 main circuit conductor, 10A first main circuit conductor, 10B second main circuit conductor, 11 main circuit conductor mounting portion, 13, 16, 17 main circuit conductor fastening portion, 14, 15 bushing mounting portion, 30 Fixed frame partition plate, 100A Switchgear room, 100B Bus room, 100C Cable Room.

Claims

1. A bushing fixed to a partition plate that separates a switchgear compartment that houses switchgear, a busbar compartment that houses busbars, and a cable compartment that houses cables, the bushing having one side to which the switchgear is connected and the other side to which main circuit conductors that are connected to the busbars and the cables are passed and attached, The bushing is composed of insulating parts divided into multiple pieces based on the main circuit conductor, and a bushing mounting portion that fixes the bushing to the partition plate and a main circuit conductor fastening portion that fastens the main circuit conductor to the bushing are located on the switchgear room side.

2. the main circuit conductors include first main circuit conductors connected to a three-phase bus bar and second main circuit conductors connected to a cable of the same phase as the bus bar, the first main circuit conductors and the second main circuit conductors of the same phase being arranged in two stages, 2. The bushing according to claim 1, wherein the bushing is configured by the insulator parts divided by a plane including the central axes of the first main circuit conductor and the second main circuit conductor of the same phase.

3. 3. The bushing according to claim 2, wherein the bushing is configured by the insulator parts divided for the first main circuit conductors and the second main circuit conductors of the same phase, and all the insulator parts have the same shape.

4. the main circuit conductors include first main circuit conductors connected to a three-phase bus bar and second main circuit conductors connected to a cable of the same phase as the bus bar, the first main circuit conductors and the second main circuit conductors of the same phase being arranged in two stages, 2. The bushing according to claim 1, wherein the bushing is configured with the insulator parts divided by a plane including the central axes of the first main circuit conductors of three phases and divided by a plane including the central axes of the second main circuit conductors of three phases.

5. 5. The bushing according to claim 4, wherein the bushing is configured by the insulating parts divided into two sections for the first main circuit conductors and the second main circuit conductors arranged in two stages, and all of the insulating parts have the same shape.

6. 6. A switchgear comprising: the bushing according to claim 1; the switchgear; a switchgear compartment that houses the switchgear; a busbar compartment that houses the busbar and a cable compartment that houses the cable; the partition plate that separates the switchgear compartment from the busbar compartment and the cable compartment; and the main circuit conductor to which the switchgear is connected on one side and to which the busbar and the cable are connected on the other side.

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